donation. 1  an act or instance of presenting something as a gift, grant, or contribution. 2  a gift, as to a fund; contribution.
A black or brown tongue typically is due to the overgrowth of bacteria that normally are present on the tongue. This, too, can be caused by the killing of some bacteria with antibiotics so other bacteria overgrow. But the most common cause of discoloration of the tongue is the overgrowth of a fungus. The most common fungus is called candida. But overgrowth of the candida fungus turns the tongue white. Infection with candida is called candidiasis, and when it happens on the tongue the condition is called thrush.
A Dr. Jonathan B. Levine, DMD, Dentist, answered. A normal tongue is pink, textured, and slightly moist. When you stick out your tongue, if you see a white coating -- that is dead bacteria that create an oxygen free zone underneath where the bad breath causing bacteria can thrive. Under this white coating, within the deep papillae of the tongue, the volatile sulfa compounds, which create the offensive odor, are produced.